"I said yes," Evans, 20, tweeted, sharing a photo of the bauble Rogers had given her.

"Tomorrow we are going to start planning!" the MTV standout added in a post later that afternoon. "OMG I've never been this happy in my life. It's like a fantasy coming true."

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Over the summer, Evans ended things with Head after he assaulted her during an altercation at a party. (In August, Radar Online reported that the mom to Jace, 3, had been granted a one-year restraining order against the former Marine.) Though she briefly reunited with ex-boyfriend Kieffer Delp in July, the on-again, off-again pair called it quits once more, and Evans began seeing Rogers in September.

While her recent tweets indicate she's in a celebratory mood post-engagement, Evans' messages about Rogers from over the weekend hint that their romance may be just as tumultuous as her relationships with Head and Delp.

On Saturday, she wrote that her "iPhone got smashed to pieces once again" and then warned, "You DEF aren't touching my body tonight, not even the touch of my skin tonight or possibility forever ..."